Testing-tank for submarines



H. E. GRIESHABER AND R. C. SIMPSON.

TESTING TANK FOR SUBMARINES.

APPLICATION FILED SEPT. 23 19M.

Patented July 15, 1919.

2 SHEETS-SHEET I -hmu 6% x Q wve 170w attouwt s THE COLUMBIA PLANQGRAPH c0., WASHINGTON, n. c

H. E. GRIESHABER AND R. C. SIMPSON.

TESTING TANK FOR SUBMARINES.

APPLICATION FILED SEPT. 28. I917.

Patented July 15, 1919.

2 SHEETS-SHEET 2.

gwvemlfo w atto'cwz Q E THE COLUMBIA PLANOORAPH co., WASHINGTON, D. c.

UNI S S ATEN T OFTC.

HUGO GRIESI-IABER AND ROBERT C. SIMPSON, OF NEW LONDON, CONNECTICUT, ASSIGNORS T0 ELECTRIC BOAT COMPANY, A CORPORATION OF NEW JERSEY.

TESTING-TAN K FOR SUBMARINES.

Specification of Letters Patent.

Patented July 15, 1919.

Application filed September 28, 1917. Serial No. 193,665.

To all whom it may concern:

Be it known that we, HUGO E. GRIESHABER, residing at New London, county of New London, State of Connecticut, and ROBERT C. SIMPsoN, residing at New London, county of New London, and State of Connecticut, have invented certain new and useful Improvements in Testing-Tanks for Submamarines; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

In testing the hull strength of a submarine boat against the crushing pressure of deep submergence for which it is designed, it has been customary to submerge it to the depth desired and maintain it at that depth for the duration of the test. Weaknesses and defects in construction have led to disastrous results because collapse at great depth has not only damaged and even destroyed the boat, but members of the crew have been injured or drowned. The present invention is predicated on the idea of reproducing the crushing effect of the pressure of deep submergence on a submarine boat in order to test its hull strength without, however, involving the serious consequences of prior practice.

Our invention embodies the idea of surrounding the submarine boat with a substantially fluid-tight envelop and supplying fluid, comprising air, or water, or both acting in conjunction, to the envelop until the pressure therein equals the pressure of deep submergenoe for which the boat is designed. Our invention also comprehends the idea of partially submerging the envelop to establish the proper line of flotation for floating the boat into it, and then sealing the envelop to inclose the boat therein in a substantially fluid-tight manner before the pressure is ap plied.

Allied to these ideas, ing and repairing a submarine boat at sea by inclosing the boat in a substantially water-tight envelop and then conducting the inspection or repairing. Preferably the envelop is partially submerged, as before, to

- submarine boat,

is the idea of inspectestablish the proper line of flotation for floating the boat into it, and the envelop 1s emptied of the water in it to expose the bottom of the boat.

The preferred form of apparatus in ac-, cordance with our invention includes a sufliciently strong tank of requisite dimensions to inclose the submarine boat for testing and repairing it. Preferably this tank is provided with one or more floats, pontoons or caissonshaving ballast and trimming tanks and flooding and emptying connections therefor, and is provided at one end with a door, preferably in the form of a separable permanently-sealed caisson having means for securing it in place in a fluid-tight manner, either on the inboard side of the opening when testing the boat, oron the outboard side when repairing it. Furthermore, there may be a trunk hatch set in the roof'of the tank intermediate its ends, so as to overlie one of the hatches of the boat in fluid-tight connection therewith, for the passage of the testing or repair crew to and from the in-- terior of the boat during the period of test.

The apparatus also includes suitable means for conducting pressure fluid to the envelop to reproduce the crushing effect of the pressure of deep submergence on the and for forcing the water out of the envelop for inspecting and re pairing the bottom of the boat.

In the accompanying drawings, illustrating the preferred form of apparatus in accordance with the present invention- Figure 1 is a top plan view of the tank; Fig. 2is a side elevation thereof, partially in section; Fig. 3 is an enlarged partial section on line 33 of Fig. 1; Fig. 4 is an end elevation of Fig. 3; Fig. 5 is an enlarged section on line 5- 5 of Fig. 2; and Fig. 6 is a detail view showing parts of Fig. 3 on an enlarged scale.

One end of the testing tank 7 is permanently closed by a wall 8. The other end has an opening 9 for the passage therethrough into the tank of a submarine boat, and is adapted to be closed in a fluid-tight manner by a closure or end gate in the form of a separable caisson 10. These parts are chanical connection withstand a bursting pressure from within, in excess of the crushing pressure which the submarine boat to be housed within it and tested is designed to withstand. The testing tank is floated on the surface of the sea by a caisson structure 11 permanently attached thereto, partitions 12 being provided between the structure 11 and the testing tank to provide a ballast tank 13 and forward and aft trimming tanks 14..

The ballast tank 13 has a sea valve 15 controlled from the top of the testing tank by an air or mechanical connection 16. It also has a valve 17, controlled from the top of the testing tank by an air or mechanical connection 18, to permit water in the ballast tank to be blown into the testing tank. Furthermore, it has an air connection 19 for admitting airunder pressure to the ballast tank to expel the water therefrom.

Each of the trimming tanks 14L is provided with a sea valve 20 controlled from the top of the testing tank by a suitable air or me- 21, and with an air connection 22 for admitting air under pressure to the ballast tank to expel the water theredesigned to from. r

The testing tank 7 is provided with a sea valve 23 controlled from the top of the testing tank by a suitable air or mechanical connection 2 1, with an air connection 25 for admitting air under pressure to the testing tank, and with a connection 26 adapted to be connected to a suitable pump (not shown) to apply pressure on the water already filling the testing tank.

The opening 9 in the testing tank is surrounded by a continuous track or rib 27 of T-form. The main body of the end gate 10 is hollow and of sufficient buoyancy to permit it to be readily floated into and out of closing position. The main body of the end gate is surrounded by a reduced marginal portion 28 which carries on its opposite sides gaskets 29 of rubber, soft wood or the like. Mounted on each side of the end gate is a plurality of pressure cylinders 30, the pistons of which are operatively connected with rocking dogs 31. As shown most clearly in Fig. 6, each dog is connected by means of a link 32 with a slide block 33 guided on a fixed track 33, the block being operatively coupled to the piston 34 of the cylinder 30 by the piston rod 35. The cylinder 30 is provided with suitable connections 36 whereby a fluid under pressure'may be admitted to one end of the cylinder or the other to move the piston therein and rock the dog toward or away from the reduced marginal portion 28 of the end gate.

The testing tank 7 is provided intermediate its ends with a trunk hatch 37 having a hatch cover 38. hatch trunk 37 is open and provided with an tion.

The lower end of the.

annular member 39 carrying gaskets 10 and 41, the gasket 1O making a water-tight joint between the hatch trunk and the member 39 therein, and the gasket 11 being adapted to engage with a coaming 4L2 or the like surrounding the conning tower hatch 13 of the submarine boat, to make a fluid-tight joint between the annular member 39' and the coaming The threaded rods 14: are provided for raising and lowering the annular member 39 toward and away from the upper edge of the coaming 42. r

The interior of the testing tank may be fitted with a suitable trackway as indicated at 15 for an overhead traveling crane, and with cradles 46 for supporting the submarine boat in the testingtank.

The operation of this apparatus is as follows: With the end gate 10 removed, the testing tank and the submarine boat are brought into axial line with the opening 9 facing an end of the boat, the various air and operating connections 16, 19, 21 and 22 of the ballast and trimming tanks 13 and 14 being operated to establish the proper line of flota- The testing tank or the submarine boat is then moved until the boat is housed with its conning tower hatch 31 below the trunk hatch 37 of the testing tank. The an nular member 39 is then lowered to make a fluid-tight joint between the interior of the trunk hatch and the interior of the testing tank. If desired, the submarine boat may be lashed or otherwise secured in place within the testing tank.

When the submarine b at is properly housed in the testing tank, the end gate 10 is floated into position to close the opening 9, the end gate being passed through the opening 9 before being brought into closing position if the testing tank is to be used to test the hull strength of the submarine'boat. As indicated in broken lines at 10 in Fig. 1, the end gate may be readily passed through the opening 9 it turned on end with its longitudinal axis substantially horizontal. the opening, it is brought into closing position by rotating it about its middle to arrange its longitudinal axis vertical as indicated in dot and dash lines at 10" in Fig. 4 and rotating it about its longitudinal axis to bring one of its gaskets 29 into engagement with the T-rib 27 surrounding the opening 9. When the end gate is thus p0- sitioned, fluid under pressure is admitted to the cylinders 30 on the outer side of the end gate to move the dogs 31 on the outer side of the end gate to locking position and hold them in th.t position to jam the end gate in place and make a joint on the outboard side of the. end gate.

The hull strength of may now be tested by water or air pressure After the end gate is passed through the submarine boat equivalent to the pressure of any submergence for which the boat is designed. If air is to be used, the required pressure may be applied and maintained at that value for the duration of the test by admitting compressed air through the connection 25. At the completion of the test the air pressure may be relieved and the boat floated out. When operating in this way, it is unnecessaryto handle the water ballast-ofthe testing tank craft except to secure and maintain a suitable line of flotation for the testing tank before and after the submarine enters. If water is to be used for applying the test to the submarine in the testing tank, then the interior of the testing tank is completely filled with water, which may be done by blowing water ballast from the ballast tank 13 to the interior of the testing tank, or by pumping water directly from the sea into the testing tank, or both. Water ballast may be blown from the ballast tank 13 to the interior of the testing tank by employing the valve controlling connection 18 and the air connection 19, and water may be pumped directly from the sea into the testing tank through the connection 26. When water is transferred from the ballast tank 13 to the interior of the testing tank, the increased buoyancy of the caisson structure which supports the testing tank compensates for the added weight of water admitted to the interior of the testing tank to apply the test pressure to the contained submarine.

The testing tank may also be used as a floating dry dock for use at sea, and when used for this purpose the end gate 10 is floated into place against the opening 9, but exterior to the testing tank, so that the gasket on the inner side of the end gate is brought against the T-rib 27 and the joint between the end gate and the rib is on the inboard side of the end gate, in which case the dogs 31 on the inner side of the end gate may be operated to make the joint water tight. When the end gate 10 has been clamped in place, the testing tank may be emptied by pumping out the water therein through the connection 26 until the bottom of the submarine is exposed and made accessible for inspection, and repairing.

What we claim is:

1. Apparatus for testing the hull strength of a submarine boat, comprising a testing tank constructed and arranged to inclose the boat and to withstand a bursting pressure in excess of the crushing pressure for which the boat is designed, buoyant means for supporting the tank at the surface of the sea, and means for transferring fluid from the buoyant means to the tank to apply pressure to the boat therein.

2. Apparatus for testing the hull strength of a submarine boat, comprising a testing tank constructed and arranged to inclose the boat and to withstand a bursting pressure in excess of the crushing pressure for which the boat is designed, buoyant means for supporting the tank at the surface of the sea, and pumping mechanism for pumping water from the buoyant means to the tank to apply pressure to the boat therein.

3. Apparatus for testing the hull strength of a submarine boat, comprising a testing tank constructed and arranged to inclose the boat and to withstand a bursting pressure in excess of the crushing pressure for which the boat is designed, ballast and trimming tanks associated with the testing tank, means for emptying and flooding the trimming tank, and means for transferring water from the ballast tank to the testing tank to apply pressure to the boat therein.

4. Apparatus for testing the hull strength of a submarine boat, comprising a testin tank constructed and arranged to inclose the boat and to withstand a bursting pressure in excess of the crushing pressure for which the boat is designed, said tank having parti tions forming a central ballast tank and fore and aft trimming tanks, means for flooding and emptying the trimming tanks, and means for transferring water from the ballast tank to the testing tank to apply pressure to the boat therein.

5. Apparatus for testing the hull strength of a submarine boat, comprising a testing tank constructed and arranged to inclose the boat and to withstand a bursting pressure in excess of the crushing pressure for which the boat is designed, said tank having a hatch adapted to communicate with a hatch of the boat in a fluid-tight manner to permit entrance into the boat and exit therefrom during the testing period, and means for conducting fluid to the tank to subject the hull of the boat to the desired pressure.

6. Apparatus of the kind described, comprising a tank body for receiving a submarine boat, and a separable permanentlysealed caisson forming a buoyant end gate for sealing the tank body in a substantially fluid-tight manner.

7. Apparatus of the kind described, comprising a tank body for receiving a submarine boat, ballast and trimming tanks for the tank body, means for flooding and emptying the ballast and trimming tanks, and a separable permanently-sealed buoyant end gate for sealing the tank body in a substantially fluid-tight manner.

8. Apparatus of the kind described, comprising a tank body having a non-circular opening at one end for receiving a submarine boat, and a removable non-circular end gate for the opening, the opening and the gate being formed in such manner that the gate may be passed through the opening from the exterior to the interior of the tank body and then rotated therein to bring the gate flat against the opening around the entire periphery thereof to close the same in a substantially fluid-tight manner.

9. Apparatus of the kind described, comprising a tank body for receiving a submarine boat, an end gate for the tank body,

and hydraulic pressure means for clamping the gate in closed position to seal the tank 10 body "in a substantially fluid-tight manner.

In testimony whereof, We affix our signatures.

HUGO E. GRIESI-IABER. ROBERT C. SIMPSON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). G. 

